at45db041b.c

C8051F005硬件SPI驱动的AT45DB041B的读写驱动

//这是主机C8051F005有硬件SPI的AT45DB041B的读写驱动
// SPI Configuration
   //SPI0CN = 0x02;    // SPI Control Register
   //MSTEN = 1;      // SPI 以主方式工作
   //SPI0CFG = 0xC7;    // SPI Configuration Register 第二边沿采样、SCK空闲高
   //SPI0CKR = 0x00;    // SPI Clock Rate Register     SPIclk=24.5M/2
   //SPIEN = 1;      // SPI0CN |= 0x01;

sbit  FLASH_CS        = P3^6;

union long_union{                         //长整形联合
   unsigned long dat;
   unsigned int  word[2];
   unsigned char byte[4];
}opcode;
 
//缓冲区1单字节写  cmd=0x84
void buff1_wr(unsigned int bfaddr,unsigned char dat){
   unsigned char i;
   opcode.byte[0]=0x84;
   opcode.word[1]=bfaddr;
   FLASH_CS=0;
   SPI0CN&=0x03;
   for(i=0;i<4;i++){SPI0DAT=opcode.byte[i]; while(!SPIF); SPIF=0;} //连续发送4个opcode
   SPI0DAT=dat; while(!SPIF); SPIF=0;                              //发送第5个字节(数据)
   FLASH_CS=1;   
}

//缓冲区1单字节读  cmd=0xd4
unsigned char buff1_rd(unsigned int bfaddr){
   unsigned char i;
   opcode.byte[0]=0xd4;
   opcode.word[1]=bfaddr;
   FLASH_CS=0;
   SPI0CN&=0x03;
   for(i=0;i<4;i++){SPI0DAT=opcode.byte[i]; while(!SPIF); SPIF=0;} //连续发送4个opcode
   SPI0DAT=0; while(!SPIF); SPIF=0; //发送第5个任意数据字节
   i=SPI0DAT;                       //清空读缓冲器
   SPI0DAT=0; while(!SPIF); SPIF=0; //启动一个字节传输
   i=SPI0DAT;                       //读缓冲器
   FLASH_CS=1;   
   return(i);
}

//Main Menory Page Program through Buffer 1 or 2
//Completes writing into selected buffer. Start self-timed erase/program operation
void page_wr(unsigned char buff_num, unsigned int bfaddr, unsigned int paddr, unsigned char *datptr, unsigned 
int len){
   unsigned char i;
   opcode.dat=paddr; opcode.dat<<=9; opcode.dat+=(bfaddr&0x1ff); //组合opcode
   opcode.byte[0]=0x82+(buff_num-1)*3;  //0x82 or 0x85
   FLASH_CS=0;
   SPI0CN&=0x03;
   for(i=0;i<4;i++){SPI0DAT=opcode.byte[i]; while(!SPIF); SPIF=0;} //连续发送4个opcode
   for(;len>0;len--){SPI0DAT=*datptr++; while(!SPIF); SPIF=0;}     //连续发送len个指定数据
   FLASH_CS=1; //Completes writing into selected buffer. Start self-timed erase/program operation
}

//Continuous Array Read (opcode: 0xe8)
//可从主存储区任意地址跨页连续读取
void array_rd(unsigned long addr, unsigned int len, unsigned char *datptr){
   unsigned char i;
   unsigned int paddr, baddr;
   paddr=addr / 264; baddr=addr % 264;
   opcode.dat=paddr; opcode.dat<<=9; opcode.dat+=baddr; //组合opcode
   opcode.byte[0]=0xe8;
   FLASH_CS=0;
   SPI0CN&=0x03;
   for(i=0;i<4;i++){SPI0DAT=opcode.byte[i]; while(!SPIF); SPIF=0;} //连续发送4个opcode
   for(i=0;i<4;i++){SPI0DAT=0; while(!SPIF); SPIF=0;}              //连续发送4个不关心字节
   i=SPI0DAT;                                                      //清空读缓冲器
   for(;len>0;len--){
      SPI0DAT=0; while(!SPIF); SPIF=0;                             //启动一个字节传输
      *datptr=SPI0DAT;                                             //读缓冲器
      datptr++;
   }
   FLASH_CS=1;
}